if f(x)=-2x-1 and g(x) =x^2-4 what is fog(-2)
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calendarEducator since 2013
write70 answers
starTop subject is Math
We need to determine the composite function.
`(f o g)(x) = f(g(x))`
`=f(x^2-4)`
It means that we need to substitute `x^2-4` in the value of x in f(x). So we have
`(f o g)(x)= -2(x^2-4)-1`
`= -2x^2+8-1`
`=-2x^2+7`
Therefore,
`(f o g)(-2) = -2(-2)^2+7`
` =-2(4)+7`
` =-8+7`
`=-1`
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calendarEducator since 2013
write464 answers
starTop subjects are Math and Science
If `f(x) = -2x -1` and `g(x) = x^2 - 4` , find `fog(-2).`
First,`fog(-2)` is equivalent to `f(g(-2)).`
Next, find `g(-2).`
`g(-2) = (-2)^2 - 4`
`g(-2) = 4 - 4`
Therefore, `g(-2) = 0.`
Now substitute 0 for g(-2) into f(g(-2)).
`f(g(-2)) = -2(0) - 1`
`f(g(-2)) = 0 -1`
Therefore, the solution for fog(-2) = -1.
calendarEducator since 2013
write455 answers
starTop subjects are Science, Math, and History
To compose a function f with a function g means to replace the argument x of f with the entire function g. Thus
fog(x) = f(g(x)) = -2*(x^2-4) -1 =-2x^2+8 -1 =-2x^2 +7
Therefore
(fog)(-2) =-2*(-2)^2 +7 =-2*4 +7 =-8+7 =-1
The answer is (fog)(-2) =-1
The answer is fog(-2) = -1.
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